1. Field of the Invention
This invention relates to a new heat exchanger system and to a new fuel control system for such a heat exchanger system as well as to new methods of making such a heat exchanger system and such a fuel control system.
2. Prior Art Statement
It is known to provide a fuel control system for a heat exchanger system that comprises a thermostat, burner means, and electrically operated igniter means for igniting fuel that issues from the burner means, the fuel control system comprising electrical circuit means that comprises an ignition trial portion for operating the igniter means, a flame sense control portion for operating the burner means, and a timer portion adapted on each cycle of closing of the thermostat and before the next opening thereof to cause the ignition trial portion to tend to operate the igniter means for a first certain period of trial time, said flame sense control portion being adapted to terminate the operation of the igniter means during the first certain period of trial time if the flame sense portion senses that fuel issuing from the burner means has been ignited, the timer portion being adapted to terminate the operation of the igniter means upon the termination of the first certain period of trial time if no flames appear at the burner means and to provide a first certain period of wait time before causing the ignition trial portion to tend to operate the igniter means for a second certain period of trial time during that cycle, the flame sense control portion being adapted to terminate the operation of the igniter means during the second certain period of trial time if the flame sense control portion senses that fuel issuing from the burner means has been ignited. For example, see the U.S. Pat. No. to Geary, 4,976,605.
For similar fuel control systems, see the U.S. Pat. Nos. to Geary, 4,836,770; 4,856,983 and 4,971,549.
Also see Chapter 8, pages 155-173 of the book, IC Timer Hand Book With One Hundred Projects And Experiments by Joseph J. Carr, published by Tab Books Inc. in 1981 for various applications of such a counter.